This is a pilot study to test a candidate intervention for age-related cognitive decline in healthy older individuals. Epidemiologic evidence suggests that cognitive training and physical exercise have positive effects on cognition and healthy elderly individuals. Evidence from animal studies indicate that enriched environment and aerobic exercise can induce changes that increase neural plasticity. We propose to test a combination of a cognitive intervention and aerobic exercise. There has been some success with previous cognitive interventions in elderly individuals, but effect sizes have been relatively small. We hypothesize that the effects of aerobic exercise on the brain can potentiate the benefit of our proposed cognitive intervention, resulting in larger effect sizes and previously seen in intervention studies. A common problem in cognitive intervention studies to date is the failure of the training to generalize to other tasks. Our proposed cognitive intervention uses emphasis change training in the context of the space fortress game, a complex and demanding video game that was specifically developed for research purposes. The emphasis change training approach has been shown to enhance attentional control and executive functions in younger individuals. Because normal aging is associated with declines in control processes and executive function, we hypothesize that enhancing these functions will result in generalized improvement across many tasks and day-to-day activities. Also, previous studies in both young and old individuals have found that the emphasis change training approach is associated with transfer of training to other tasks. Ninety elders will be randomized into three study arms: control, space fortress training alone, and space fortress training within the exercise. The formal intervention period, conducted in the laboratory and fitness center, will be three months, with pre- and post-testing. In order to test the feasibility of maintenance of treatment over long periods of time, participants completing this additional training period will continue their respective training program at home for one year. Compliance will be monitored and the efficacy of this long- term training will be assessed. PUBLIC HEALTH RELEVANCE: Evidence from animal and human studies strongly suggests that aerobic exercise and cognitive stimulation have a beneficial effect on cognition, but intervention studies in healthy elders have not shown large improvements, and these improvements have not transferred to day-to-day activities. The goal of the proposed study is to evaluate the benefit of a combination of aerobic exercise and a cognitive intervention designed to enhance executive control processes. This combined intervention may provide enhanced benefits, and the targeted cognitive functions may enable generalization of training to many other tasks and activities. The possibility that this intervention may markedly improve day-to-day function in healthy elders has enormous potential significance for public health.